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Decimal to Hexadecimal Program - Java Program

Design a class DeciHex to accept a positive integer in decimal number system from the user and display its hexadecimal equivalent.

Example 1:
Decimal number = 25
Hexadecimal equivalent = 19

Example 2:
Decimal number = 28
Hexadecimal equivalent = 1C

Some of the members of the class are given below:

Class name: DeciHex

Data members/instance variables:
num: stores the positive integer
hexa: string to store the hexadecimal equivalent of num

Methods/Member functions:
DeciHex(): constructor to initialize the data members with legal initial values
void getNum(): to accept a positive integer
void convert(int n): to find the hexadecimal equivalent of the formal parameter ‘n’ using the recursive technique

void display(): to display the decimal number and its hexadecimal equivalent by invoking the function convert()

Specify the class DeciHex giving details of the constructor(), void getNum(), void convert(int) and void display(). Define a main() function to create an object and call all the functions accordingly to enable the task.

Java

import java.util.Scanner;
class DeciHex{
    int num;
    String hexa;
    public DeciHex(){
        num = 0;
        hexa = "";
    }
    public void getNum(){
        Scanner in = new Scanner(System.in);
        System.out.print("Decimal number = ");
        num = Math.abs(Integer.parseInt(in.nextLine()));
    }
    public void convert(int n){
        if(n == 0)
            hexa = "0";
        else{
            int d = n % 16;
            if(d < 10)
                hexa = d + hexa;
            else{
                switch(d){
                case 10:
                    hexa = "A" + hexa;
                    break;
                case 11:
                    hexa = "B" + hexa;
                    break;
                case 12:
                    hexa = "C" + hexa;
                    break;
                case 13:
                    hexa = "D" + hexa;
                    break;
                case 14:
                    hexa = "E" + hexa;
                    break;
                case 15:
                    hexa = "F" + hexa;
                    break;
                }
            }
            if(n / 16 > 0)
                convert(n / 16);
        }
    }
    public void display(){
        convert(num);
        System.out.println("Decimal number = " + num);
        System.out.println("Hexadecimal equivalent = " + hexa);
    }
    public static void main(String[] args){
        DeciHex obj = new DeciHex();
        obj.getNum();
        obj.display();
    }
}

Output

 
OUTPUT 1:
Decimal number = 25
Decimal number = 25
Hexadecimal equivalent = 19


OUTPUT 2:
Decimal number = 28
Decimal number = 28
Hexadecimal equivalent = 1C